A typical sound converter (for example, a microspeaker, etc.) does not use a broadband sound source due to communication technology limitations. However, with the development of the information communication technology, the reproduction bandwidth of the sound source to be reproduced in the sound converter has been widened, and with the increase of the required power, the structure of the typical sound converter has limitations in terms of characteristics and reliability.
In order to solve these problems, the present applicant filed and registered Korea Patent No. 10-1200435, entitled by “High power microspeaker” (hereinafter, referred to as ‘the conventional patent’), which includes a frame, a protector, a yoke assembly coupled to the frame and having a magnet, a diaphragm disposed in the frame to generate vibration, a voice coil coupled to the diaphragm to vibrate the diaphragm, a terminal disposed at one side of the frame to provide electrical connection between a lead wire of the voice coil and an external terminal, and a damper formed of an FPCB having an inner part to which a center diaphragm, a side diaphragm and the voice coil are attached, an outer part to which the side diaphragm is attached and which is brought into contact with the frame and the protector, a support part which serves to connect the voice coil, the outer part and the inner part and which includes a land part to which a lead-in wire of the coil is soldered or welded, and a connection part which extends to the outside of the outer part and which provides electrical connection between the terminal disposed at the frame and the outer part.
The conventional patent of the present applicant has a limitation in suppressing split vibration because the vibration system is composed of the diaphragm, the damper formed of the FPCB and the voice coil, with a small distance between the diaphragm and the damper and with a relatively large distance to the lower end of the voice coil in which motion is generated by a magnetic force.
In addition, the conventional patent of the present applicant has a risk of thermal deformation because the fresh air does not smoothly flow into the diaphragm.